"Although the chance of a disaster to planet Earth in a given year may be quite low, it adds up over time, and becomes a near certainty in the next thousand or 10 thousand years."

"I have spent my life traveling across the universe, inside my mind."

"There are no boundaries to human endeavor. We are all different. However bad life may seem, there is always something you can do and succeed at. While there's life, there is hope."

"When I gave a lecture in Japan, I was asked not to mention the possible re-collapse of the universe, because it might affect the stock market. However, I can reassure anyone who is nervous about their…"

"So my friend tried to call me the other week... but all he was getting was an automated answer."